As that I have both the CH and the SD cores. I can tell you what it boils down to.
It really depends on the stepping as to how well it will OC. most SD cores have issues with Cold bug and cant handle much more the just water or air cooling. it takes a special core for it to do so. Most on...
I will post a pic of the proc later tonight and list the full steping. Yes it has been Oced about 2 or 3 times for very breif moments to bench with. Best on Dry Ice was 3825mhz.